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U.  S.  DEPARTMENT   OF    AGRICULTURE. 

OFFICE  OF  EXPERIMENT  STATIONS-FARMERS'  INSTITUTE  LECTURE  No.  6. 
K.   C.  TRUE,  Director. 


SYLLABUS  OF  ILLUSTRATED  LECTURE 


OX 


ESSENTIALS 


OP 


SUCCESSFUL  FIELD  EXPERIMENTATION. 


BY 


C.  E.  THORNE,  M.  S.  A., 

Director  Ohio  Agricultural  Experiment  Station,  Wooster,  Ohio. 


^< 


\\i 


WASHINGTON: 

OOVEBNMENT    PRINTING    OFFICE 

1905. 


848 


U.  S.  DEPARTMENT    OF    AGRICULTURE, 

OFFICE  OF  EXPERIMENT  STATIONS— FARMERS'  INSTITUTE  LECTURE  No.  6. 


A.    C.    TRUE,   Director. 


SYLLABUS  OF  ILLUSTRATED  LECTURE 


ON 


ESSENTIALS 


OF 


SUCCESSFUL  FIELD  EXPERIMENTATION. 


BY 


C.  E.  THORNE,  M.  S.  A., 

Director  Ohio  Agricultural  Experiment  Station,  Wooster,  Ohio. 


WASHINGTON: 

GOVERNMENT    PRINTING    OFFICE, 

1905. 


PREFATORY  NOTE 


This  syllabus  of  a  lecture  upon  Essentials  of  Successful  Field  Experi- 
mentation, by  C.  E.  Thome,  M.  S.  A.,  director  of  the  Ohio  Agricul- 
tural Experiment  Station.  La  accompanied  by  32  views  illustrating  the 
methods  recommended  for  conducting  agricultural  experiment  work. 

The  s}Tllabus  and  views  have  been  prepared  for  the  purpose  of  aiding 
farmers'  institute  lecturers  in  their  presentation  of  this  subject  before 
institute  audience-.  This  subject  is  especially  timely  because  of  the 
rapid  increase  now  taking  place  in  the  number  of  field  experiments  in 
which  farmers  are  cooperating  with  the  experiment  stations. 

The  numbers  in  the  margins  of  the  pages  of  the  syllabus  refer  to 
similar  numbers  on  the  lantern  slides  and  to  their  Legends  as  given  in 
the  Appendix. 

In  order  that  those  using  the  lecture  may  have  opportunity  to  fully 
acquaint  themselves  with  the  subject,  reference-  to  its  recent  literature 
are  given  in  the  Appendix. 

John   Hamilton. 
Farmer?  Institute  Specialist. 
Recommended  for  publication. 

A.  C.  True,  Director. 
Publication  authorized. 

James  Wilson.  Secretary  of  Agriculture. 
Washington,  D.  C,  November  J,  1905. 

(2) 


ESSENTIALS  OF  SUCCESSFUL  FIELD  EXPERIMENTATION. 


By  C.  E.  Thorne,  M.  S.  A. 


INTRODUCTION. 

The  experiment  station  is  the  distinguishing  feature  of  the  new 
agriculture.  It  stands  for  organized  research  in  agriculture,  for  the 
concentration  of  the  knowledge  and  skill  and  energy  of  the  entire 
State  on  the  solution  of  the  unsettled  problems  of  the  farm. 

The  experiment  station  is  created  to  do  things  which  are  impossible 
to  the  ordinary-  farmer.  It  is  furnished  with  costly  equipment  and  is 
conducted  by  men  trained  in  the  methods  of  scientific  research,  who 
are  made  free  from  other  cares  in  order  that  they  may  devote  their 
undivided  energies  to  helping  the  farmer. 

But  while  there  are  some  things  which  can  only  be  done  by  the  aid 
of  such  an  equipment  as  that  of  the  experiment  station,  there  are 
other  things  which  the  station  can  never  do,  and  the  farmer  who 
profits  most  by  the  work  of  the  experiment  station  is  he  who  is  him- 
self an  experimenter. 

It  is  the  province  of  the  experiment  station  to  discover  and  formu- 
late general  principles.  The  application  of  these  principles  must  be 
made  by  the  farmer  himself.  Even  were  there  an  experiment  station 
in  every  county,  there  would  still  be  hundreds  of  farms  within  each 
county  on  which  some  of  the  conditions  would  vary  from  those  of  the 
station,  and  while  no  farmer  should  attempt  to  duplicate  the  elaborate 
work  of  the  experiment  station,  neither  can  any  farmer  afford  to 
blindly  accept  the  conclusions  reached  at  the  experiment  station  with- 
out subjecting  some  of  them  to  the  test  of  further  investigation  on  his 
own  farm. 

Were  there  no  other  reason  for  this  than  the  benumbing  effect 
upon  the  intellect  produced  by  the  unthinking  acceptance  of  the  dicta 
of  others,  as  evidenced  by  the  unnumbered  centuries  during  which  the 
sickle  remained  unchangingly  a  chief  implement  of  husbandly,  this 
unchangeableness  in  implements  s}Tmbolizing  a  similar  monotony  in 
the  farmer's  intellectual  processes,  that  alone  would  be  abundantly 
sufficient.  The  farmer  of  to-day  must  learn  to  think  or  he  is  lost,  and 
nothing  is  more  conducive  to  exact  thinking  than  scientific  experiment. 

(3) 


The  experiment  station  should  carry  its  work  far  enough  to  demon- 
strate clearly  the  lines  which  practical  application  must  follow,  but 
after  it  has  reached  its  uttermost  limit  there  will  still  be  much  for  the 

fanner  to  do. 

Many  experiments  which  farmers  attempt,  however,  are  either  vtA- 
ueless  or  actually  misleading,  because  of  failure  to  observe  some  of  the 
essentia]  conditions  of  successful  experimentation:  for  investigation  in 
agriculture  by  experiment  is  a  business  by  itself  entirely  distinct  from 
ordinary  farming,  and  many  a  good  farmer  will  overlook  points  of 
vital  importance  to  the  success  of  an  experiment  until  his  attention  is 
called  to  them.  It  is  in  the  hope  of  encouraging  farmer-  to  experi- 
ment more  largely  and  to  assist  them  in  making  their  experimental 
work  more  effective  that  the  following  suggestions  are  offered: 

SELECTION  OF  SOIL. 

A  matter  of  first  importance  in  preparation  for  tield  experiment  is 
that  the  soil  shall  he  as  nearly  uniform  as  possible  in  character.  To 
secure  such  uniformity  the  following  points  should  be  considered: 

GEOLOGICAL  HISTORY. 

View. 

1  It  is  important,  in  experiments  with  fertilizers  especially,  to 

know  whether  a  soil  is  of  sedentary,  drift,  or  alluvial  origin; 
that  is,  whether  it  has  been  formed  by  the  gradual  weathering  of 
the  underlying  rocks;  by  the  action  of  the  great  glaciers  which 
once  overspread  the  northern  portion  of  the  United  States,  grind- 
ing up  the  rocks  over  which  they  passed  and  rearranging  their 
particles  in  the  moraines  and  sheets  of  drift  which  they  left  he- 
hind  them  as  they  retreated  northward,  or  by  the  action  of  the 
flood  waters  of  rivers  and  streams,  washing  down  the  soil  from 
the  higher  lands  and  depositing  it  in  the  alluvial  flood  plains  or 
"bottom  lands"  of  the  streams — a  force  which  is  in  active  opera- 
tion to-day  -as  this  knowledge  may  throw  considerable  light 
upon  different  methods  of  treatment. 

A  sedentary  soil  is  likely  to  be  more  uniform  than  a  drift  or 
alluvium,  because  in  the  case  of  these  transported  soils  there  is 
generally  a  more  or  less  uneven  deposit  of  materials,  an  excess 
of  gravel  and  coarse  sand  appearing  in  one  spot  and  of  silt  and 
finer  particles  in  another.  A  heavy  sheet  of  drift  may  some- 
times become  weathered  into  practically  the  same  condition  a-  a 
sedentary  soil,  while  it  would  seem  that  some  of  the  great  loess 
deposits  would  offer  especially  good  conditions  to  the  Held  ex- 
perimenter, the  loes^  being  the  fine-grained,  silty  soils  found  in 
some  of  the  Western  States,  and  whose  origin  is  apparently  due 
to  the  blowing  of  the  dry  surface  dust  into  banks  and  hillocks, 
sometimes  many  feet  in  depth. 


PREVIOUS  MANAGEMENT. 

View. 

It  is  also  important  to  know  something  of  the  previous  man-         2 
agement  of  the  soil.     The  great   Rothamsted  experiments  have 
shown  the  persistence  of  the  effect  of  applications  of  barnyard         3 
manure  -the  yield  from  a    formerly   manured   plat  remaining 
more  than  double  that  of  the  unmanured  land  alongside  for         4 
thirty  years  after  the  manuring  had  been  discontinued.     Other 
illustrations  arc  given  to  show  the  effect  of  leaving  fence  rows 
or  lanes  uncultivated  for  a  period  of  years  and  then  bringing 
them  into  comparison  with  lands  brought  under  cultivation  at 
an  earlier  date.     Again,  a  tree  which  has  stood  for  years  after 
the  remainder  of  the  forest  has  been  cleared  away,  and  whose 
shade  has  been  a  resting  place  for  live  stock,  may  cause  a  con- 
siderable variation  in  the  productiveness  of  the  soil  which  will 
be  manifest  long  after  it  shall  have  been  cut  away. 

TOPOGRAPHY. 

Absolutely  level  land  is  seldom  adapted  to  field  experiment,  5 

for  the  reason  that  no  land  is  so  flat  that  it  does  not  have  slight 
inequalities  of  surface,  and  on  such  land  the  minor  depressions 
receive  a  larger  share  of  the  rainfall  by  surface  drainage  from 
the  higher  portions  and  thus  have  an  advantage  in  dry  seasons 
when  water  may  be  the  controlling  factor  in  producing  increase 
of  crop,  while  they  may  be  at  a  disadvantage  in  seasons  of 
excessive  rainfall.  When  the  subsoil  is  porous  these  depres- 
sions may  merely  be  a  little  more  fertile  than  the  higher  por- 
tions through  increased  accumulation  of  humus,  but  if  the 
subsoil  be  impervious  to  water  it  may  give  rise  to  a  semiaquatic 
growth  of  vegetation  which  may  radically  modify  the  behavior 
of  the  soil  under  cropping.  On  the  other  hand,  steep  hillsides 
are  not  adapted  to  experiment,  because  the  water  from  heavy 
rainfalls  in  washing  over  them  will  cut  them  into  gullies  or 
transport  fertilizing  materials  from  plat  to  plat. 

The  ideal  topography  for  field  experiment  is  a  broad,  gentle 
slope  of  about  1  to  2  per  cent,  or  just  enough  to  permit  the 
surplus  water  of  heavy  rains  and  melting  snows  to  flow  off 
uniformly  and  completely. 

ARRANGEMENT    OF   PLATS. 

SIZE  OF  PLATS. 

Farmers  generally  have  the  idea  that  experiment  plats  should 
be  made  as  large  as  possible,  an  idea  naturally  following  their 
observation  of  the  inequalities  of  most  soils;  but  the  practical 


6 

difficulty  in  the  way  of  using  large  plate  is  the  fact  that  fora 
comparative  experiment  the  soil  most  be  a-  Dearly  absolutely 
uniform  as  possible,  and  it  Lb  extremely  difficult  to  find  1 
areas  having  sufficient  uniformity.  In  almost  all  cases  it  will 
be  found  better  t<>  use  a  large  Dumber  of  small  plat-  than  a 
-mall  Dumber  of  Large  plat-,  since  by  multiplying  the  plats  the 
variation-  <>f  the  -oil  can  be  more  evenly  distributed.  A  field 
of  LO  acres,  for  example,  in  which  it  i-  desired  to  make  tea 
comparisons,  will  yield  results  of  far  greater  value  if  cut  into 
LOO  plats  containing  one-tenth  acre  each.  gii  ing  ten  plat-,  dis- 
tributed over  the  field,  to  each  particular  comparison,  than  if 
only  LO  plats  are  employed. 

The  most  convenient  size  of  plat-  for  computation  is  one-tenth 
acre.  When  the  plats  are  reduced  much  below  one-tenth  acre 
in  size  another  (dement  enters  into  the  problem,  namely,  the 
individuality  of  the  plant.  One-tenth  acre  of  corn,  as  usually 
planted,  will  contain  nearly  a  thousand  plants,  and  this  number 
ought  he  grown  from  a  single  seed  ear:  hut  experiment-  have 
shown  that  ears  taken  from  the  same  variety  and  grown  on 
neighboring  stalks   may    vary   50   per   cent    in   their  produce. 

6  Hence,  even  for  plat-  of  one-tenth  acre,  the  greatest  care  -hould 
be  taken  to  secure  seed  which  has  been  drawn  from  a  consider- 
able number  of  ears  and  thoroughly  mixed.  In  the  case  of 
wheat  or  oat-  a  tenth-acre  plat  may  contain  from  100,000  to 
150,000  plants,  the  seed  of  which  has  probably  been  obtained 
from  3,000  to  5.0o0  heads  of  grain,  representing  several  hun- 
dred separate  plants.  Hence,  we  may  safely  use  a  -mailer  plat 
for  the  small  grains  than  for  corn. 

SHAPE   OF  PLATS. 

7  It  is  generally  conceded  that  experiment  plats  should  be  long 
and  narrow,  both  for  greater  convenience  of  cultivation  and 
also  because  tins  shape  permit-  a  better  arrangement  with 
respect  to  irregularities  of  soil.  The  minor  inequalities  of  the 
soil  are  usually  caused  by  the  gradual  washing  of  the  surface 
into  small  ridge-  and  valleys,  which  can  be  bo  crossed  by  a  long 
and  narrow  plat  a-  to  cover  equal  portion-  of  the  lower  and 
higher  land,  whereas  this  would  not  be  so  readily  accomplished 
in  square  plats.  It  is  well  to  adapt  the  width  of  the  plat  to 
that  of  the  machinery  in  use.  A  plat  l»i  feet  wide,  for  exam- 
ple, will  contain   four  rows  of  corn  4  feet  apart,  or  live   I 

of  potatoes  38  inches  apart  It  may  be  -own  with  three 
'•through-*'  of  an  8  hoe.  8-inch  drill,  and  cut  in  three  swaths 
with  a  machine  having  a  5j  <>r  6  foot  cutter  bar.     The  width 


of  the  plats  should  also  be  adjusted  to  the  drainage.     When      View- 
they  are  more  than  16  feet  wide  it  will  be  necessary  on  most 
soils  to  give  each  plat  a  separate  drain. 

SURFACE   DRAINAGE. 

Whatever  the  natural  topography  of  the  land  may  be,  under  8 

most  circumstances  the  uniform  disposal  of  excess  of  surface 
water  ma}'  be  facilitated  by  a  slight  ridging  of  the  plats,  such  9 

as  is  accomplished  by  plowing  the  plats  separately.  To  attain 
this  end  successf  \i\\\  the  plats  should  be  comparatively  narrow, 
in  order  that  the  cross  harrowing  may  so  distribute  the  ridge 
left  by  the  plow  as  to  leave  a  gradual  slope  from  the  middle  of 
the  plat  to  the  sides.  On  wide  plats  there  will  always  be  a  flat 
space  left  between  the  ridge  and  the  furrow. 

It  is  not  necessary  nor  advisable  to  repeat  the  ridging  at  every 
plowing.  On  the  contrary,  the  effect  of  ridging  will  remain 
apparent  for  five  to  ten  years,  even  though  subsequent  plo wings 
and  cultivations  be,  as  they  should  be  whenever  practicable, 
across  the  plats. 

CROSS  DRAINAGE. 

One  of  the  chief  objects  in  separating  the  plats  by  dead  fur- 
rows is  to  prevent  cross  drainage  of  surplus  rainfall.  Where 
there  are  no  surface  drains  such  water  will,  of  course,  follow  the 
natural  slopes  of  the  land,  and  these  are  practically  never  suffi- 
ciently- regular  for  the  purpose  of  plat  experiment.  In  variety 
testing  and  cultural  work  this  may  not  always  be  a  matter  of 
great  importance ;  but  in  fertilizer  tests  it  is  essential  that  the 
fertilizer  applied  to  each  separate  plat  be  confined  to  that  plat, 
which  can  not  be  the  case  if  the  surface  water  is  permitted  to 
flow  indiscriminately  across  the  plats. 

Even  in  such  work  as  variety  testing,  however,  it  is  desirable 
that  the  surface  water  find  its  way  off  the  plat  as  quickly  as 
possible.  If  it  stands  in  minor  depressions  over  the  plat  it  will 
cause  irregularities  in  yield  ;  if  the  plats  are  laid  off  up  and  down 
a  slope  the  water  will  follow  down  the  drill  rows,  washing  out 
many  plants  during  the  spring  thaw,  while  if  the  plats  are  laid 
off  across  the  slopes  there  will  be  cross  washing  which,  in  fer- 
tilizer comparisons,  will  vitiate  the  results.  The  best  arrange- 
ment in  such  work  is  to  so  ridge  the  plats  that  the  surface  water 
will  flow  from  the  middle  down  the  sides  of  the  plats  into 
dividing  furrows,  these  being  so  graded  as  to  carry  it  gently 
away.  Some  gullying  of  the  furrows  is  almost  unavoidable, 
but  it  is  better  there  than  within  the  plat  itself. 


CROSS  FEEDING. 


Another  prime  object  of  a  furrow  between  the  plats  is  to  pre- 
vent cross  feeding-  that  Lb,  the  extension  of  the  roots  from  an 
unfertilized  plat,  for  instance,  to  one  that  has  been  fertilized — 
and  this  is  practically  accomplished  by  the  ordinary  dead  furrow. 

UNDERDRAINAGE. 

10  Provision  for  the  removal  of  an  excess  of  soil  water  is 
lately  essential  to  successful  field  experiment.     Such  excess  may 
be  naturally  removed  by  stratified  rocks  Lying  at  Bhallow depths 
below  the  surface,  or  in  rare  instances  deposits  of  gravel  may 

he  found  sufficiently  uniform  to  serve  this  purpose,  hut  in  the 
vast  majority  of  cases,  especially  with  -oils  which  have  been  so 
long  in  cultivation  that  a  hardpan  has  been  formed,  it  will  he 
necessary  to  aid  nature  by  artificial  drainage. 

In  draining  for  plat  experiment  the  drains  should  be  so  lo 
as  to  give  uniform  drainage  to  each  plat  When  the  plats  do 
not  exceed  a  rod  in  width  and  the  -oil  i-  reasonably  porous,  a 
single  drain  may  serve  two  plat-,  being  located  under  the  divis- 
ion space  between  them,  but  in  the  majority  of  cases  it  would  be 
better  to  give  each  plat  its  separate  drain,  located  either  under 
the  dividing  space  or  under  the  middle  of  the  plat.  The  former 
location  is  probably  the  better  one  where  it  is  not  designed  to 
study  the  composition  of  the  drainage  waters,  as  the  surface 
water  accumulating  in  the  furrow  will  be  more  promptly  removed 
if  the  drain  lies  immediately  beneath  the  furrow  than  if  it  lies 
under  the  middle  of  the  plat. 

DIVISION   SPACES. 

11  Division  spaces  2  feet  in  width  have  been  found  sufficient  for 
the  separation  of  the  plats,  even  in  fertilizer  tests,  provided 
the  land  is  plowed  in  ridges  with  the  dead  furrows  falling  at  the 
division  .-paces.  Such  narrow  space-  necessitate  special  care  in 
seeding  in  order  that  the  grain  may  not  be  sown  too  far  down  in 
the  furrow.  The  dead  furrow  is  rightly  named,  and  in  propor- 
tion as  the  seed  falls  within  its  influence  will  the  growth  of  the 

12  plant  be  diminished.  When  the  division  space  is  not  more  than 
'1  feet  wide  and  the  planting  is  accurately  done,  the  resulting 
produce  will  probably  be  a  more  accurate  index  of  what  might 
be  expected  under  ordinary  field  culture,  under  the  same  treat- 
ment, than  where  the  spaces  are  wider,  as  in  the  latter  case  the 
outside  rows  will  have  a  larger  area  for  root  extension,  before 
reaching  the  dead  furrow,  than  in  the  former. 


OLD   RIDGES   AND   DEAD   FURROWS. 

View. 

It  is  of  prime  importance  to  so  arrange  the  plats  as  to  avoid  13 
the  errors  arising  from  old  ridges  and  dead  furrows,  for  either  a 
ridge  or  a  furrow,  running  lengthwise  in  a  plat,  may  completely 
reverse  the  results  of  the  test.  Wherever  possible,  experiment 
plats  should  be  laid  out  across  the  direction  in  which  the  field 
has  previously  been  plowed. 

CHECK   PLATS. 

A  matter  of  great  importance,  too  often  lost  sight  of  in  field 
experiments,  is  the  repetition  of  check  plats.  In  the  most 
uniform  soils  there  will  be  some  variation  in  the  produce  of 
adjoining  plats  from  season  to  season.  Even  were  the  actual 
plant  food  the  same,  the  variations  in  level  which  occur  on  all 
soils  will  produce  an  unequal  distribution  of  moisture,  and 
moisture  may  often  be  a  more  important  factor  in  determining 
crop  yield  than  plant  food.  The  ideal  system  of  plat  experi- 
ment would  leave  every  alternate  plat  as  a  check.  Next  to  this 
comes  the  plan  of  leaving  every  third  plat  as  a  check,  thus  hav- 
ing a  check  plat  on  one  side  or  the  other  of  every  plat  under 
treatment.  In  fertilizer  tests  the  check  plats  ma}^  be  unfertilized 
or  subjected  to  uniform  dressings  with  a  standard  fertilizer  or 
manure,  depending  upon  the  object  of  the  experiment.  In 
variety  tests  the  check  plats  should  be  planted  to  a  standard 
variety.  The  importance  of  repetition  of  check  plats  will  be 
further  illustrated  under  the  head  of  calculating  increase. 

PERMANENT   BOUNDARIES. 

A  plat  of  land  designed  for  experiment  should  be  definitely 
marked  with  permanent  stakes,  especially  if  tests  with  fertilizers 
are  to  be  made.  A  very  convenient  marking  stake  for  such 
purposes  is  a  piece  of  second-hand  gas  pipe,  about  2, feet  long, 
driven  to  such  a  depth  that  harvesting  machinery  will  pass  over 
it.  A  block  of,  say,  ten  plats  may  be  marked  with  such  stakes, 
set  at  the  corners  of  the  block,  the  intervening  distances  to  be 
measured  for  each  planting. 

HEADLANDS   AND   ROADWAYS. 

Ample  headlands  should  be  left  across  the  ends  of  every  block 
of  experiment  plats.  Not  only  are  these  headlands  needed  to 
prevent  the  breaking  down,  in  turning  while  cultivating,  such 
crops  as  corn  or  potatoes,  but  they  are  required  in  the  harvest- 
ing of  the  small  grains,  in  order  that  the  machine  may  be  driven 

11361— No.  6—05 2 


10 

View.  around  tin-  plats  empty,  and  they  arc  e\  en  more  urgently  needed 
in  plowing,  as  the  trampling  of  the  soil  by  the  team  in  turning 
the  j>l<>\\  will  materially  affect  the  yield  of  the  following  crop. 
These  headlands  may  be  made  18  feet  wide,  but  20  feet  is  better. 

14  In  addition  to  the  headlands  there  should  be  roadway-  at  in- 
tervals through  every  large  group  of  plats,  to  permit  the  first 

15  passage  of  the  machine  in  harvesting,  or  the  continual  pa— 'nil:* 
where  it  is  necessary  to  cut  the  grain  l>ut  one  way.  and  the  pas- 

1(>  sage  of  wagons  in  hauling  manure  or  grain.  An  experiment 
plat  should  never  be  used  as  a  roadway,  for  the  reason  given 
above,  that  the  additional  trampling  and  packing  by  the  team 
and  wheels,  even  in  the  driest  weather,  will  so  change  the 
physical  condition  of  the  soil  as  to  affect  the  future  yield  of 
crop-.  A  convenient  arrangement,  where  the  plats  are  not  more 
than  16  feet  wide,  is  to  leave  a  12-foot  roadway  between  blocks 
of  eight  or  ten  plats.  These  roadways  may  be  planted  in  the 
same  crop  as  that  grown  on  the  plats,  the  roadways  to  he  cut  out 
and  the  produce  set  to  one  side  where  it  will  not  be  mixed  with 
that  of  the  plats  before  the  harvesting  of  the  latter  i-  begun. 

The  headlands,  however,  should  be  kept  in  grass,  in  order 
that  the  plats  may  at  all  times  be  accessible.  Nothing  will  add 
so  much  to  the  interest  in  and  value  of  an  experiment  as  to  be 
able  to  visit  it  at  any  time  and  to  see  clearly  the  contrast  between 
plats.  It  is  not  waste,  but  economy,  to  give  a  little  land  to  this 
purpose. 

LABEL  STAKES. 

IT  Every  plat  should  be  distinctly  marked  with  a  label  stake, 

18  giving  the  number  of  the  plat  and  an  indication  of  its  treatment. 
A  very  convenient  stake  for  this  purpose  is  a  board  4  inches 
wide  and  30  inches  long,  sharpened  at  one  end.  painted  with 
three  coats  of  white-lead  paint,  and  lettered  with  price  markers 
or  with  brush.  Such  stakes,  if  taken  up  and  sheltered  through 
the  winter,  will  last  ten  years  or  more. 

PREPARATION  OF  LAND  FOR  CROPS. 

UNIFORM  PLOWING. 

It  is  highly  important  that  the  plowing  and  fitting  of  the  land 
for  a  comparative  experiment  he  as  uniform  as  possible  in  every 
respect.  A  difference  of  a  few  weeks  in  date  of  plowing  may 
cause  as  great  a  difference  in  yield  of  crop  as  will  he  produced 
by  difference  in  fertilizing,  and  far  greater  than  is  usually 
observed  between  varieties.  For  this  reason  the  plowing 
should,  as  a  rule,  be  done  across  tin1  plats,  and  when  it  becomes 


11 

necessary  to  plow  the  plats  separately,  in  order  to  ridge  them,      view- 
the  work  should  be  pushed  forward  as  expeditiously  as  possi- 
ble.    On  this  account  it  is  well  to  have  the  plats  arranged  in 
blocks  of  ten,  planning  the  test  so  that  each  block  will  have  its 
complete  series  of  checks,  independently  of  the  others. 

MANURING  OR  FERTILIZING. 

Both  manures  and  fertilizers  may  be  distributed  b}r  machinery 
more  uniformly  and  accurately  than  by  hand.  In  a  compara- 
tive test  of  manures  or  fertilizers  it  is  important  that  the  mate- 
rial be  kept  entirely  on  the  plat,  leaving  the  dividing  spaces 
entirely  untouched;  but  where  the  test  is  one  of  varieties  or 
methods  of  culture  the  entire  surface  ma}^  be  covered.  In 
applying  fertilizers  it  is  a  good  plan  to  bring  the  applications 
intended  for  the  different  plats  all  to  the  same  bulk,  by  mixing 
them  with  diy  sand,  so  that  a  single  setting  of  the  drill  may 
suffice  for  the  entire  experiment.  Even  then  it  will  not  always 
be  possible  to  exactly  gauge  the  materials,  for  mixtures  which 
are  largely  made  up  of  such  salts  as  sodium  nitrate  and  potas- 
sium chlorid  will  pass  through  the  drill  less  readily  than  those 
which  contain  a  larger  proportion  of  sand.  It  is  a  good  plan 
to  test  the  drill  by  sowing  an  equal  bulk  of  material  on  a  plat 
not  designed  for  experiment  before  beginning  the  actual  work. 
The  fertilizer  will  run  more  slowly  as  the  drill  becomes  nearly 
empty;  hence  it  is  well  to  set  the  drill  so  that  a  little  will  be  left 
in  it  after  the  plat  has  been  gone  over,  and  then  turn  back  over 
the  work  until  all  is  out. 

Machines  are  now  made  for  distributing  fertilizers  and  lime  19 
broadcast.  They  are  made  wider  than  the  ordinary  fertilizer 
drill  and  are  guaranteed  to  spread  even  slaked  lime  satisfac-  20 
torily.  Where  such  a  machine  is  not  available,  the  manure 
spreader  may  be  used,  first  spreading  a  layer  of  chaff  or  similar 
material  in  the  bottom  of  the  machine  and  spreading  the  lime 
on  this.  Where  small  quantities  of  lime  are  to  be  applied — 
1,000  pounds  or  less  per  acre — it  will  be  an  advantage  to  gear 
the  machine  so  that  the  apron  will  travel  more  slowly  than  in 
ordinary  work.  The  best  manure  spreaders  are  now  fitted  with 
hoods  and  slow  gearing  for  lime  spreading. 

MACHINES  SHOULD  BE  ACCURATE. 

While  a  good  machine  will  do  better  work  than  can  be  done 
by  hand,  there  are  many  machines  in  use  which  are  not  fit  for 
experimental  work.  There  are  both  corn  planters  and  grain 
drills  which  do  not  distribute  the  seed  uniformly,  while  there 
are  othei's  which  are  unsuited  to  the  experimenter's  purpose 


12 

u<u-  because  they  are  too  difficult  to  clean  out,  thus  greatly  increas- 
ing the  difficulty  of  making  variety  tests.  In  thrashing,  this 
last  difficulty  is  still  more  conspicuous.    The  modern  thrashing. 

machine  IS  gotten  .up  at  a  Low  cost  and   intended  only  for  rapid 

work  on  a  Large  scale,  and  is  altogether  unsuited  to  the  separa- 
tion of  different  varieties  of  grain.  The  older  thrashing  ma- 
chines, with  the  t  raveling  apron,  are  better  adapted  to  this  work 

than  the  modern  machine.  There  should  he  no  place  for  grains 
to  Lodge   in  passing   through    the    machine,  hut    it    should    he  so 

constructed  that  every  grain  entering  the  cylinder  will  be 
promptly  carried  through  the  machine  and  out  at  the  proper 
place.  It  is  possible  to  do  this,  hut  of  course  the  cost  of  the 
machine  will  he  increased. 

SELECTION  OF  SEED. 

21  The  selection  of  the  seed  is  a  very  important  matter  in  field 

experimentation.  Defective  seed  means  an  imperfect  stand, 
and  an  imperfect  stand  means  an  unreliable  experiment,  for  no 
method  of  calculation  yet  known  will  correct  the  inequalities 
of  an  irregular  stand.  Not  only  should  the  seed  he  strong  in 
vitality,  but  it  should  be  uniform  in  size,  because  such  uniform- 
ity not  only  is  necessary  to  uniformity  in  distribution  by  ma- 
chinery but  also  to  uniformity  in  growth  of  the  young  plants. 
For  this  reason  the  seed  corn  should  be  selected  from  the  mid- 
dle of  the  ear,  rejecting  the  butts  and  tips,  and  whea  and  oats 
and  other  small  grains  should  be  carefully  graded  bypassing 
them  through  a  fanning  mill  and  over  a  sieve,  which  will  take 
out  the  small  and  imperfect  grains. 

THE  ROWS  SHOULD  BE  STRAIGHT. 

That  rows  should  be  straight  applies  even  more  forcibly  to 
the  small  grains  than  to  corn,  for  a  careless  driver  who  allows 
his  rows  to  run  together  by  so  much  reduces  the  yield  of  the 
plat,  as  experiments  have  shown  that  where  the  quantity  of 
seed  passes  above  a  certain  maximum  -and  the  regular  seeding 
should  be  near  this  maximum — then  the  yield  falls  oil';  so  that 
when  two  rows  are  run  together  not  only  do  we  lose  all  the 
produce  of  one  of  the  rows  but  part  of  that  of  the  other. 

THE  ENTIRE  PLAT  SHOULD  BE  PLANTED. 

In  drilling  the  small  grain-,  most  drills  will  travel  a  short  dis- 
tance before  the  seed  reaches  the  ground.  If  the  drill  is  started 
at  the  exact  end  of  the  plat,  therefore,  there  will  be  a  short 
space  unsown.     To  guard  against  this  the  drilling  should  extend 


13 

beyond  the  ends  of  the  plats,  the  excess  being"  cut  away  before  View- 
the  plat  itself  is  harvested.  The  best  way  to  accomplish  this  is 
to  stretch  a  line  between  the  stakes  marking  the  corners  of  a 
block  of  plats,  and  with  a  hoe  cut  out  a  narrow  strip  under  the 
line.  The  nose  of  a  machine  may  then  be  made  to  follow  this 
strip,  thus  quickly  cutting  away  the  excess,  which  of  course 
must  be  kept  out  of  reach  of  those  who  haul  in  the  grain,  if 
the  trimming  has  been  left  until  harvest  time,  but  the  better 
wa}r  is  to  trim  the  plat  ends  while  the  crop  is  still  green,  making 
hay  of  the  produce.  Not  only  will  this  method  remove  all  dan- 
ger of  mixing  the  results,  but  it  will  add  to  the  satisfaction  of 
watching  the  maturing  of  the  different  plats. 

PLANTING  AND  CULTIVATION. 
MACHINE  WORK   PREFERABLE. 

Wherever  possible  machinery  should  be  used  in  planting  and 
cultivating.  There  is  no  longer  any  question  as  to  the  supe- 
riority of  drilling  the  small  grains  over  sowing  them  broadcast, 
and  the  same  principles  apply  to  the  corn  planter,  at  least,  if 
not  also  to  the  potato  planter.  Certainly  the}7  do  to  the  tobacco 
planter.  The  seed  grain  is  deposited  more  uniformly  by  the 
drill  or  planter,  whether  as  to  quantity  of  seed,  depth  of  plant- 
ing, or  uniformity  of  covering,  than  can  be  done  by  hand. 
Even  the  hand  corn  planter  is  better  than  dropping  the  seed  by 
hand  and  covering  with  the  hoe,  while  a  man  and  two  boys  will 
set  tobacco  or  cabbage  plants  not  only  very  much  more  rapidly 
but  also  much  better  with  the  machine  on  which  they  all  ride, 
carrying  with  them  a  barrel  of  water  which  automatically 
deposits  a  cupful  at  uniform  distances  in  the  row,  the  boys 
alternately  placing  a  plant  in  the  freshly  opened  furrow  just 
as  the  water  reaches  it,  while  the  machine  closes  the  furrow  and 
presses  the  earth  around  the  plant. 

In  cultivating,  and  especially  in  harvesting,  machinery  is 
essential  to  accurate  work.  An  experiment  with  cereals  is 
incomplete  unless  the  proportion  of  straw  or  stover  to  grain 
is  determined,  and  it  is  practically  impossible  to  secure  uni- 
formit}7  of  stubble,  either  of  small  grains  or  corn,  by  hand 
cutting. 

In  thrashing  the  small  grains  no  one  would  now  think  of  using 
the  flail  where  it  was  desired  to  make  an  accurate  determination 
of  the  separate  product  of  straw  and  grain.  With  corn,  how- 
ever, thrashing  machinery  has  not  yet  reached  a  stage  at  which 
it  can  successfully  compete  with  hand  husking. 


L4 

HARVESTING. 
CUTTING  GRASS  PLATS. 

lii!  In  experiment- with  crops  grown  in  rotation  the  grass  and 

clover  crops  usually  occupy  the  dividing  spaces,  as  well  as  the 
plats  pmper.  A  convenient  and  fairly  accurate  method  of  har- 
vesting such  plats  is  to  drive  the  machine  to  -take-,  so  Bet  that 
the  point  of  the  machine  will  just  reach  the  outside  of  the  plat 
A  careful  driver  with  a  steady  team  can  thus  (ait  a  swath  as 
straight  a-  though  a  line  had  been  stretched.  After  the  out- 
side- are  thus  cut,  the  cutting  out  of  the  middle  i-  a  simple 
matter.  The  dividing  spaces  should  he  left  uncut  until  the  ha-- 
has been  taken  up  from  the  plats. 

HARVESTING  SMALL  GRAINS. 

23  When   plats  of  small  grains  are  arranged  in  blocks,  as  has 

been  above  recommended,  the  roadway-  are  first  cut  out.  the 
ends  of  the  plats  straightened,  if  this  has  not  previously  been 
done,  after  which,  if  the  grain  be  not  lodged,  the  machine  may 
cut  up  one  side  of  the  block  and  down  the  other,  running  empty 
across  the  ends,  of  course,  but  a  man  should  follow  the  machine 
to  remove  the  residue  that  may  be  left  on  it  as  it  leaves  the  plat 
and  to  see  that  each  sheaf  is  finally  left  on  the  plat  to  which  it 
belongs. 

HARVESTING  CORN. 

24  The  corn  harvester  will  no  doubt  come  into  general  use  be- 
cause of  its  great  saving  in  labor  and  because  of  its  uniform 
stubbles,  but  in  experiment  work  it  is  indispensable  that  a 
gleaner  should  closely  follow  the  harvester  in  order  to  pick 
up  dropped  stalks  and  ears  which  may  be  broken  otf  and  keep 
them  on  their  proper  plats. 

HARVESTING   POTATOES. 

Potatoes  may  be  harvested  with  the  potato  digger  with  a  fair 
degree  of  accuracy  by  harrowing  the  ground  after  all  the  pota- 
toes thrown  out  by  the  digger  have  been  taken  care  of.  and 
picking  up  those  exposed  by  the  harrow.  The  advantage  of 
machine  over  hand  work,  however,  is  much  less  decided  in 
handling  the  potato  crop,  whether  in  planting  or  harvesting, 
than  in  case  of  grain  and  grass  crops. 


15 

WEIGHING. 
THE  WAGON  AND  STOCK  SCALE. 


View. 


The  wagon  and  .stock  scale  of  about  4  tons  capacity  is  found  on 
many  farms  and  is  indispensable  where  feeding  experiments 
are  being  made.  With  such  a  scale  the  relative  weights  of 
grain  and  straw  may  be  ascertained  with  a  fair  degree  of  accu- 
racy by  weighing  the  grain  in  the  straw  on  the  wagon  as  it 
is  being  drawn  to  the  thrasher  and  again  weighing  the  grain 
as  it  comes  from  the  machine,  the  weight  of  the  straw  being 
found  by  the  difference. 

Several  plats  may  be  carried  at  once  by  separating  them  with 
sheets,  reweighing,  of  course,  after  each  plat  is  unloaded.  In 
the  same  manner  several  plats  of  hay  may  be  brought  in  at  once, 
especially  if  the  hay  sling  be  used  for  unloading. 

THE  PORTABLE  DERRICK  SCALE. 

The  portable  derrick  scale  is  an  implement  much  less  expen-       25 
sive  than  the  wagon  scale  and  at  the  same  time  more  accurate. 
It  consists  of  a  derrick,  similar  in  construction  to  the  oil  or  gas 
well  derrick,  but  only  8  feet  high  and  corresponding^  light  in 
construction,  and  mounted  on  a  pair  of  sled  runners. 

This  derrick  scale  is  especiall}7  useful  in  weighing  the  corn 
crop  where  it  is  husked  in  the  field,  as  it  may  follow  the  huskers, 
weighing  the  stover  before  it  is  reshocked,  and  by  means  of  a 
light  platform  or  large  basket,  substituted  for  the  hay  sling, 
weighing  the  grain  as  it  goes  into  the  wagon.  It  may  also  be 
similarly  used  for  weighing  potatoes  as  they  are  harvested. 

REWEIGHING. 

The  most  careful  people  make  mistakes  sometimes,  and  the 
produce  of  every  plat  in  experimental  work — at  least  the  grain 
and  potatoes — should  be  weighed  the  second  time.  To  accom- 
plish this  the  grain  as  it  comes  from  the  thrasher  is  weighed 
into  sacks;  these  are  tagged  with  the  number  of  the  plat  and 
set  aside,  to  be  weighed  again  when  there  is  less  hurry  than  while 
the  thrashing  is  in  progress.  In  a  similar  manner  potatoes  and 
corn  may  be  gathered  into  tagged  sacks,  boxes,  or  barrels,  and 
weighed  again.  Both  potatoes  and  corn  should  be  separated 
into  large  and  small,  and  in  the  case  of  corn  it  is  advisable  to 
count  the  ears,  nubbins,  and  stalks,  separating  these  into  those 
which  bear  one  ear,  those  having  two  ears,  and  those  which  are 
ba'rren. 


L6 

KEEPING  THE  RECORDS. 
PLANS,  DIAGRAMS,  ETC. 

26  Before  a  field  experiment  is  begun  the  laud  available  should 
be  carefully  measured  and  a  diagram  of  the  experiment  drawn 
to  scale  on  paper.  In  connection  with  this  diagram  there  should 
be  a  record  hook  in  which  should  be  entered  the  dates  of  all 
operations  and  other  items  bearing  upon  the  progress  of  the 
experiment,  including  the  final  outcome.  It  i>  never  safe  to 
depend  upon  memory  nor  upon  field  stakes  for  the  plan  of  the 
experiment;  for  memory  is  proverbially  treacherous  and  stakes 
are  liable  to  he  misplaced  or  lost.  A  very  convenient  way  of 
entering  the  final  results  of  an  experiment  which  is  continued 
from  year  to  year  is  shown  in  the  accompanying  transcript 
from  an  actual  record. 

CORRECTING  RESULTS. 

27  While  it  is  highly  desirable  that  an  experiment  should  be  so 
conducted  that  its  results  may  be  accepted  just  a<  they  come 
from  the  field,  there  will  sometimes  be  cases  where  some  cor- 
rection is  needed  in  order  to  avoid  a  statement  that  would  be 
actually  misleading.  In  the  case  of  corn  and  potatoes  especially 
it  is  practically  impossible  to  secure  at  all  times  a  perfect  stand, 
because,  of  destruction  of  occasional  plants  by  insects  or  from 
other  causes.  Where  such  cases  occur  it  has  been  found  better 
to  count  the  hills  or  plants  and  make  the  corrections  on  the 
basis  of  the  average  stand  actually  attained,  rather  than  upon 
that  of  the  possible  full  stand.  The  former  method  gives 
results  corresponding  to  the  yield  actually  obtained,  whereas 
the  latter  one  always  gives  exaggerated  results,  since  it  appears 
that  the  destruction  of  a  plant  gives  opportunity  for  surround- 
ing plants  to  develop  more  freely  and  produce  a  yield  larger 
than  could  have  been  attained  under  normal  conditions. 

CALCULATING  INCREASE. 

28  An  old  soil  which,  from  surface  indications,  is  apparently 
uniform,  may  nevertheless  show  considerable  variations  due  to 
previous  treatment.  This  is  shown  by  the  accompanying  dia- 
gram, which  shows  the  average  yield  of  four  plats  which  have 
received  for  ten  years  fertilizers  containing  the  same  quantities 
each  of  nitrogen,  phosphorus,  and  potassium,  together  with  the 
yields  of  three  adjoining  unfertilized  plats,  the  plats  being 
arranged  as  indicated  by  the  numbers.     It  will  be  seen  that 


17 

where  we  assume  the  variation  between  consecutive  unfertilized  View- 
plats  to  be  uniformly  progressive  we  get  a  practically  uniform 
increase  from  the  different  fertilizers,  but  if  we  should  strike  a 
general  average  of  all  the  unfertilized  plats  there  would  be  no 
consistency  in  the  results.  The  variation  in  the  unfertilized 
yield  in  this  case  was  due  to  the  fact  that  the  land  occupied  by 
plat  28  and  parts  of  the  adjacent  plats  was  not  brought  into 
cultivation  until  many  years  after  that  occupied  by  the  other 
plats  of  the  series;  but  about  seven  years  before  the  test  began 
all  had  been  thrown  into  the  same  field,  and  when  the  test 
began  there  was  no  superficial  indication  of  previous  differences 
in  treatment. 

CONTINUITY  OF  WORK. 

Few  of  the  questions  which  demand  solution  by  field  experi- 
ment can  be  definitely  answered  by  a  single  season's  test.  The 
unequal  effect  of  rainfall  on  soils  differently  situated  with 
respect  to  natural  drainage  may  produce  wide  differences  in  the 
apparent  results  of  a  test  in  different  seasons.  Other  climatic 
variations  may  produce  similar  variations  in  results,  so  that  an 
experiment  must  be  carried  through  a  number  of  seasons  before 
its  results  can  be  accepted  as  a  reliable  guide. 

This  point  is  illustrated  by  a  test  showing  the  increase  or  29 
decrease  in  yield  of  wheat  on  several  plats  in  1894,  and  in  the 
average  for  ten  years.  It  will  be  observed  that  in  the  general 
average  acid  phosphate  and  nitrate  of  soda  are  the  most  effective 
constituents  of  the  fertilizer,  but  that  their  effect  has  varied 
greatly  in  different  seasons,  acid  phosphate  producing  an  actual 
loss  of  crop  in  1894.  Had  this  experiment  been  limited  to  a 
single  test  in  1894  it  is  evident  that  a  wholly  erroneous  opinion 
of  the  effect  of  acid  phosphate  on  this  soil  would  have  been 
formed. 

Views  29,  30,  and  31  show  the  varying  effect  of  fertilizers  30 
over  a  long  period  of  years  on  poor  soil  and  on  good  soil.  In 
most  of  these  seasons  phosphorus  is  unmistakably  the  chief  31 
agent  in  producing  increase  of  crop;  but  in  1894,  on  the  poor 
land,  potassium  takes  the  leading  place,  and  in  1903  nitrogen 
comes  to  the  front,  while  on  the  good  land  there  has  been  still 
greater  variability  in  the  apparent  effect  of  the  three  fertilizing 
constituents. 

Another  reason  for  continuity  of  work  in  experiments  with       32 
fertilizers  is  the  fact  that  the  full  effect  of  such  fertilizers  is  sel- 
dom realized  in  the  crop  to  which  they  are  applied.     This  point 
is  shown  by  a  table  giving  the  average  increase  from  fertilizers 
in  a  test  which  has  been  in  progress  for  ten  years,  the  figures 


18 

opposite  each  year  being  the  average  result  for  the  entire  period 
up  to  and  including  that  season.  In  this  case  there  was  b  com- 
paratively Bteady  yield  on  the  unfertilized  plat,  with  a  constantly 
Increasing  yield  from  the  fertilizers. 

SUMMARY. 

The  experiment  station  Btands  for  organized  research,  doe-  things 
impossible  to  the  ordinary  farmer,  and  formulates  general  principle-. 
The  farmer  must  make  the  application.  The  farmer  who  profits  most 
by  the  experiment  station  must  himself  be  an  experimenter. 

SELECTION    OF    SOIL. 

The  geological  history  of  a  soil  is  of  importance  as  an  index  t<>  its 
genera]  character.  Pn  vious  managt  rru  nt  may  have  an  important  bear- 
ing upon  the  result^  of  an  experiment,  as  shown  by  long-continued 
effect  <>f  manuring  at  Rothamsted.     In  topography  an  experiment  field 

should  not  be  absolutely  level  nor  very  Bteep;  a  broad,  gentle  slope 

of  1  or2  per  cent,  or  just  enough  to  permit  uniform  surface  drainage, 
has  been  found  best. 

ARRANGEMENT   OF   PLATS. 

The  most  convenient  size  of  plate,  for  most  purposes,  is  one-tenth 
acre.  This  size  is  convenient  for  computation,  and  holds  a  sufficient 
number  of  plants  to  eliminate  the  errors  arising  from  individuality  if 
care  be  taken  in  seed  selection.  The  inequalities  of  soil  can  be  tx 
eliminated  by  duplicating  the  test  in  small  plats  than  by  the  m 
large  plats.  In  ,sj,<ij>,.  the  plats  should  be  long  and  narrow.  It  is 
well  to  adjust  the  width  to  the  convenient  use  of  machinery  and  to  the 
scheme  of  drainage. 

Surfod  (1  r<t>i)<t<i<  must  be  provided  for.  and  this  can  be  most  easily 
done  by  making  the  plats  comparatively  narrow  and  slightly  ridging 
them.  Underdravnagi  is  absolutely  necessary  on  most  soils.  Divis- 
ion spaces  need  not  be  more  than  '2  feet  wide,  provided  they  are  the 
dead  furrows  made  in  ridging  the  plats.  o/J  ridges  and  dead  far* 
rows,  when  running  lengthwise  of  a  plat,  may  reverse  the  result- 
test,  hence  plats  should  be  laid  out  across  the  direction  of  previous 
plowings.  Gross  drainage  should  be  carefully  avoided  in  fertilizer 
tests.  Cross  feeding  may  be  prevented  by  separating  the  plats  by 
dead  furrows.  The  repetition  of  check  j>hits  is  a  matter  of  first  impor- 
tance. Every  third  or  fourth  plat  should  be  used  a-  a  check.  The 
boundaries  of  every  block  of  experiment  plats  should  be  permanently 
marked  with  stakes  that  will  not  be  thrown  out  in  plowing.  R 
lands  >m<l  roadways  should  be  left  around  every  block  of  eight  or  ten 
plats,  SO  that  teams  may  be  turned  without  trampling  the  plats,  and 
every  plat  -hould  be  distinctly  marked  with  a  label  stake. 


19 

PREPARATION   OF  LAND  FOR  CROPS. 

Uniformity  of  treatment  is  of  first  importance.  A  difference  of  a 
few  days  or  weeks  in  date  of  plowing  may  cause  as  great  a  difference 
in  yield  as  any  difference  in  variety  or  fertilizing.  Manures  and  fer- 
tilizers should  l)c  applied  by  machinery,  with  special  care  to  get  each 
application  wholly  on  its  plat  and  uniformly  distributed.  Lime  may 
be  applied  with  a  special  lime  distributor  or  with  manure  spreader. 
All  machinery  should  be  accurate,  whether  for  seeding,  harvesting,  or 
thrashing.  Selection  of  seed  is  a  matter  of  importance.  Seed  of  low 
vitality  will  not  give  a  proper  stand,  nor  will  seed  that  is  uneven  in 
size,  hence  the  tips  and  butts  of  seed  corn  should  be  rejected  and  the 
small  grains  should  be  graded.  The  rows  should  be  straight,  especially 
with  the  small  grains,  for  when  the  rows  crowd  each  other  the  yield 
will  be  reduced.  The  entire  plat  shoidd  be  planted,  and  to  accomplish 
this  the  small  grains  should  be  drilled  beyond  the  plats,  cutting  away 
the  excess  before  harvest. 

PLANTING  AND  CULTIVATING. 

Machine  work  is  preferable  wherever  it  can  be  employed,  as  it  is 
more  accurate  and  uniform  than  hand  work,  whether  for  planting, 
cultivating,  harvesting,  or  thrashing. 

HARVESTING. 

Gmss  plats  may  be  mown  by  driving  the  machine  to  stakes  set  so 
that  the  nose  of  the  machine  will  just  reach  the  outer  edge  of  the  plat. 
For  harvesting  grain  crops  the  plats  should  be  arranged  in  blocks  of 
eight  or  ten,  with  12-foot  roadways  between,  so  that  the  machine  need 
not  be  driven  over  the  plats  except  when  actually  cutting.  In  all  cases 
a  gleaner  should  follow  the  machine,  to  keep  the  produce  of  each  plat 
on  the  plat  itself. 

WEIGHING. 

Hay  and  grain  may  be  weighed  on  the  ordinary  wagon  and  stock 
scale.  Several  plats  may  be  loaded  on  the  wagon,  separating  them  by 
sheets,  and  weighing  again  after  each  one  is  unloaded  ;  but  a  cheaper, 
and  better  weighing  arrangement  is  the  portable  derrick  scale,  a  com- 
mon weighbeam  suspended  to  the  shorter  end  of  a  long  lever,  which 
is  pivoted  on  a  small  derrick  carried  on  a  sled  and  moved  from  place  to 
place  as  needed.  All  weights  of  grain  or  potatoes  should  be  verified 
by  setting  the  produce  of  each  plat  aside  in  a  tagged  sack  or  barrel  and 
reweighing  at  leisure. 


20 


KEEPING  THE  RECORDS. 


A  complete  plan  of  each  experiment  should  be  made  on  paper  before 

the  work  in  the  field  LS  begun,  and  every  operation  should  be  entered 
in  a  record  book  kept  for  the  purpose.  It  is  sometimes  necessary  to 
correct  th<  results,  said  it  is  better  to  base  this  correction  upon  the 
average  actual  yield  rather  than  the  possible  full  yield.  The  calcula- 
tion of  mcreast  should  be  made  on  the  assumption  that  the  variation 
between  neighboring  check  plats  is  due  to  similar  variations  in  the 
soil  between  them.  It  is  never  safe  to  assume  that  one  or  two  cheek 
plats  will  sufficiently  indicate  the  character  of  the  soil  of  a  large  field, 
nor  that  the  general  average  of  a  series  of  Buch  plats  will  do  -<>. 

CONTINUITY  OF  WORK. 

This  is  of  first  importance  in  field  experiment.  The  results  of  one 
season's  tests  may  be  the  direct  opposite1  of  the  average  outcome  of  a 
period  of  years,  and  as  a  general  rule  the  full  effect  of  a  fertilizer  or 
manure  can  only  be  determined  after  a  series  of  year-. 


APPENDIX, 


TiANTERK  SLIDES.     • 

No.  of 
view. 

1.  Soil  formation. 

Face  of  a  stone  quarry  in  a  glaciated  district,  showing  the  heavy  layers  at  the  bottom, 
gradually  breaking  up  into  thinner  layers  toward  the  surface,  and  finally  ending  in  a  finely 
broken  stratum,  over  which  is  spread  the  thin  drift  sheet  with  its  contained  pebbles  and 
small  bowlders.  In  many  places  in  this  region  this  drift  sheet  is  replaced  by  a  thin  soil  filled 
with  the  angular  fragments  of  the  underlying  rock— such  a  soil  as  would  be  made  by  a  little 
further  disintegration  of  the  upper  stratum  of  rock  shown  in  the  picture. 

2.  Persistence  of  effect  of  barnyard  manure. 

Compiled  from  Memoranda  of  the  Rothamsted  Experiments,  1903,  pp.  26,  27.  Experiments 
on  the  growth  of  barley  in  Hoosfield. 

3.  Effect  of  previous  treatment  of  land. 

A  diagram  showing  the  yield  of  the  unfertilized  plats  in  an  experiment  in  which  corn,  oats, 
wheat,  clover,  and  timothy  have  been  grown  in  a  five-year  rotation  for  ten  years.  There  are 
30  plats  in  the  series,  and  every  third  plat,  beginning  with  No.  1,  has  been  left  continuously 
unfertilized.  The  average  yield  of  these  plats  ranges  between  1,400  and  1,750  pounds  per  acre 
until  No.  28  is  reached,  when  it  suddenly  mounts  to  nearly  2,600  pounds.  This  experiment 
was  located  in  a  field  which  had  been  in  cultivation  for  fifty  years  or  more,  and  at  the  time  it 
was  laid  out  no  difference  was  apparent  between  the  land  occupied  by  plat  28  and  other  por- 
tions of  the  field;  but  it  was  afterwards  learned  that  this  plat  and  parts  of  the  adjacent  plats 
had  been  occupied  by  a  lane  until  some  seven  years  before  the  test  began. 

4.  Old  fence  rows  are  rich. 

This  point  is  again  brought  out  in  the  photograph  showing  the  growth  of  corn  on  an  old, 
roadside  fence  row,  in  a  region  where  the  discovery  has  recently  been  made  that  it  is  cheaper 
to  fence  cattle  in  than  to  fence  them  out,  and  consequently  the  fences  are  being  limited  to 
such  as  are  necessary  to  inclose  permanent  pastures,  and  many  miles  of  road  are  entirely 
unfenced. 

5.  An  ideal  platting  field. 

Part  of  a  field  of  about  60  acres  which  is  wholly  devoted  to  plat  experiments.  It  slopes 
gradually  toward  the  north,  with  secondary  slopes  toward  the  east  and  west,  which  give  suf- 
ficient fall  for  the  lateral  tile  drains  that  are  laid  between  the  plats,  running  east  and  west 
and  emptying  into  mains  which  run  to  the  north— one  on  each  side  of  the  field. 

6.  A  tenth-acre  plat  of  oats. 

Showing  the  great  difference  in  number  of  individual  plants. 

7.  Mowing  a  plat  of  grass  16  feet  wide  in  3  swaths. 

8.  Effect  of  ridging  on  wide  and  narrow  plats. 

No.  1  shows  a  plat  2  rods  in  width,  as  first  plowed,  and  No.  2  shows  the  same  plat  after  the 
harrow  has,gone  over  it,  partly  leveling  the  ridge  or  back  furrow.  Nos.  3  and  4  show  a  plat 
1  rod  wide  under  similar  conditions.  It  will  be  observed  that  In  the  narrower  plat  the 
effect  of  cross  harrowing  is  to  leave  a  surface  having  a  gradual  slope  from  the  crest  to  the 
furrow,  whereas  on  the  wide  plat  there  will  be  a  flat  space  left  between  the  two.  The  prac- 
tical difference  between  the  two  methods  of  platting  is  that  the  surplus  water  of  heavy  rains 
and  melting  snows  will  flow  off  the  narrow  plat  more  uniformly  and  with  less  cross  washing 
and  gullying  than  off  the  wider  one. 

9.  Contour  of  a  plat  18  feet  wide  from  center  to  center  of  furrow  as  obtained  in 

actual  practice.     These  plats  have  just  been  ridged  for  the  third  time  in  12 

years.     Future  crosswise  plowing  will  materially  reduce  the  height  of  the 

ridges. 

(21) 


22 

■- 

tO.     Natural  rmderdrainage. 

There  las  gradual  transition  here  bom  the  heavy  layers  <>f  stratified  rock,  through  the 
lighter  layers  and  broken  strata  to  tin-  thin  sheet  ol  soil,  irhieh  has  been  funned  bj  tfa 
(feathering  of  the  surface  rock.  On  ttii-  soil  treei  are  growing,  which  send  their  root* 
through  ti>  the  rocki  below.  When  the  treei  arc  cut  away  their  decaying  roots  furnish  nat- 
urul  drainage  channel*  to  the  rock  seams  below .  but  tbeee  channels  are  gradually  obliterated 
by  the  Mraping  of  the  plow  and  the  trampling  of  the  teams  and  grazing  stock.  Eventually 
i  bardpan  li  formed,  and  the  land  require!  artificial  drainage.    From  Ohio  sta.  Bui.  no. 

l  i.    Two-fool  wide  dividing  space  between  plate  of  coin. 

12.  Two-foot  wide  dividing  >pa<  «•  between  plats  of  <>ata. 

13.  Bffed  of  backfuTTOw. 

The  middle  row  of  corn  in  the  picture  la  located  on  the  ridge  or  backfurrow  formed  by 
throwing  two  furrows  together,  it  a  ill  be  Been  if  one  plat  has  men  a  backfurrow  and  others 
do  not.  the  apparent  results  of  ■  comparative  tc^t  may  be  very  misleading    The  effect  of  »n 

old  dead  farrow  may  be  equally  fatal  to  accuracy  in  n-Milts. 

11.     Arrangement  of  |>lat<  for  t-year  rotation. 

Four  ranges  or  tiers  of  plats,  in  plats  each,  as  actually  employed  in  an  experiment  in  which 
corn,  oats,  wheat,  and  clover  are  grown  in  rotation,  each  CTOp  being  grown  every  year. 

15.  Arrangement  of  plats  for  3-year  rotation. 

Six  blocks  of  10  plats  each  arranged  for  a  8-year  rotation. 

16.  Plats  arranged  for  blocks  of  ten. 

No.  16  shows  40  plats  arranged  in  blocks  of  m  plats  each  and  being  one  of  three  simi'. 
tions  used  in  a  3-year  rotation.  The  arrangement  shown  in  No.  15  or  No.  16  permits  thi 
rate  handling  of  each  block  of  10  plats,  each  having  its  compl-  (hecks,  and  is  the 

better  arrangement  where  circumstances  permit  its  nee.  The  plats  marked  X  are  cheek  plats, 
to  be  left  unfertilized  in  fertilizer  tests  or  planted  with  the  same  variety  in  variety  com- 
parisons. 

17.  Label  stakes. 

A  convenient  label  stake  4  inches  wide  by  30  inches  long,  painted  white  and  lettered  with 
a  brush.  These  label  stakes  are  useful,  but  should  never  be  permitted  to  take  the  place  of  a 
written  record  on  a  carefully  drawn  diagram,  as  stakes  may  be  easily  transposed  or  lost. 

18.  A  signboard  for  convenience  of  visitors. 

19.  Distributing  lime  with  lime  spreader. 

20.  Spreading  lime  with  the  manure  spreader. 

21.  Seed  corn. 

Four  grains  each  from  butt,  middle,  and  tips  of  same  ear,  showing  difference  in  size. 

22.  Catting  the  grass  plats. 

After  careful  measurement  from  the  permanent  iron  stakes  which  mark  the  corners  of  each 
block  of  10  plats,  small  stakes  are  driven  at  the  proper  points  on  opposite  sides  of  the  block. 
The  machine  is  then  set  with  the  tongue  over  the  stake  on  the  opposite  side  of  the  block  and 
is  driven  to  a  tall  stake  held  by  a  boy  at  the  end  in  the  foreground.  The  lx>y  has  just  stepped 
aside  to  let  the  team  pass.  Returning,  the  two  machines,  driven  full,  will  cut  the  Lrra-s  stand- 
ing on  the  plat,  leaving  the  2-foot  wide  dividing  space  uncut.  This  will  stand  until  the 
hay  on  the  plat  is  weighed. 

2.'3.     Harvesting  the  small  grains. 

This  is  a  simpler  matter  than  harvesting  the  hay,  as  no  grain  stands  in  the  dividing  s] 
but  a  man  or  boy  should  follow  the  machine  to  see  that  every  sheaf  is  placed  on  its  proper 
plat  and  that  the  machine  is  cleared  of  grain  when  it  reaches  the  end  of  the  plat. 

24.  Harvesting  the  com  plats. 

In  harvesting  the  corn  plats  with  a  harvesting  machine  an  ear  will  occasionally  be  knocked 
off.  A  man  should  follow  the  machine  to  see  that  all  such  ears  are  placed  on  their  proper 
plats. 

25.  The  derrick  scale. 

The  Bled  runners  are  oak  joists  2  inches  thick.  10  inches  wide,  and  8  feet  long:  the  uprights 
are  of  any  Strong  WOOd  '2  by  1  inches  ami  8  feet  long;  at  tin-  top  they  are  bolted  to  a  head- 
6  Inches  thick.  8  Inches  wide,  and  is  indies  long.  The  swivel  or  rowlock  which  carries 
the  pole  is  made  by  a  blacksmith,  the  ears  being  i  inch  by  2  inches,  and  the  tongue  1J  inches 
In  diameter  by  8  inches  Long.  The  swivel  re^ts  upon  a  washer  let  into  tlie  headpiece,  and 
the  split  key  which  holds  the  swivel  in  place  works  upon  a  similar  washer  fitted  in  the  lower 
side  of  the  headpiece.    The  pole  is  24  feet  long  and  4  inches  in  diameter  at  the  swivel. 


23 

No.  of 
view. 

26.  Planning  a  field  experiment. 

27.  Method  of  recording  plat  work. 

28.  Calculating  the  increase'. 

When  every  third  plat  is  a  check  plat  the  difference  in  yield  between  two  successive  checks 
is  found,  and  one-third  of  this  difference  Is  added  t<  <  t  ix-  smaller  yield  of  the  two  checks  or 

subtracted  from  the  larger  yield,  the  result  being  assumed  to  be  the  natural  yields  of  the  two 
plats  lying  between  the  cheeks.  The  difference  between  this  assumed  yield  and  the  yield 
actually  obtained  is  taken  as  the  increase  or  decrease  resulting  from  treatment. 

29.  Effect  of  fertilizers  in  different  seasons. 

This  table  shows  a  decrease  in  yield  on  all  plats  fertilized  with  acid  phosphate  in  1894  except 
one,  although  this  material  has  increased  the  yield  every  year  since  then. 

30.  The  varying  effect  of  the  different  fertilizing  constituents  in  successive  seasons 

on  poor  soil. 

31.  The  varying  effect  of  the  different  fertilizing  constituents  in  successive  seasons 

on  good  soil. 

These  show  the  necessity  for  continuous  work  over  a  long  period  of  time  before  definite 
conclusions  are  drawn. 

32.  Progressive  increase  from  fertilizers. 

The  cumulative  effect  of  systematic  fertilizing  is  shown  by  this  table,  each  season's  increase 
being  sufficient  to  raise  the  average  increase  for  the  total  period  to  a  higher  level. 


i:i:i  1:1:1. n«  E8. 

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Relating  to  Maintenance  or  [ncreaae  of  Boil  Fertility,  by  C.  E.  Thome. 
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Oorn  ( Hilture,  by  J.  I.  Schulte. 
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En  in    E.    Kuril. 

Connecticut   Stoma  Sta.   Bpt   L888,   p.   17.    Cooperative   Field   Experimenta  with 

Fertilizers,  bj  0.  B.  Phelps. 
Georgia  Bta.  Bui.  65.    Corn  Culture,  by  II.  J.  Bedding. 

gia  Ma.  Bul.  *'»*''.    Cotton  Culture,  by  It.  .1.  Bedding. 
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pp.  23. 
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conducted  on  the  Farm  and  in  the  Laboratory  of  Sir  J.  B.  Lawes  at  Rothamsted, 

1900,  pp.  119. 
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Sta.  Rec,  10,  p.  955.)  T  ' 

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Sci.,  1899,  pp.  19-27.     (Expt.  Sta.  Rec,  12,  p.  337.) 
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(Expt.  Sta.  Rec,  16,  p.  859.) 
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pp.  1-45.     (Expt.  Sta.  Rec,  13.,  p.  726.) 
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